My fry don't get live food beyond infusoria when they're young. I feed decap bse and then frozen foods at first.
They get live black worms when they're about half an inch/can eat them when I cut them up.

If you have a petstore who sells reptiles you can usually get an ounce of live black worms for $3 or less, just keep them in the fridge when not feeding. These are what I used to condition.